PubMed Health⌕ Search

Biomedical subjects

Alain C Borczuk

Publications and source records attributed to Alain C Borczuk.

At least 19 recordsLinked to original sources
PubMed2007

Expression profiling and lung cancer development.

Recent lung cancer research has been directed to using molecular approaches to facilitate early diagnosis, to identify clinically relevant biological factors associated with histologic heterogeneity, and to identify novel therapeutic agents. This research takes advantage of technical advances that allow rapid high throughput assays to interrogate the genome, proteome, and epigenome. In this review of gene expression profiling in lung carcinogenesis, we will focus upon recent advances in the understanding of malignant transformation of lung epithelial cells and of lung cancer differentiation and progression. These studies have provided important information about the genomic alterations of tobacco smoke-associated airway field carcinogenesis and about the developmental pathways that mediate lung tumor invasion and histologic differentiation in response to injury.

Adenocarcinoma↗
PubMed2006

Epigenetic inactivation of Betaig-h3 gene in human cancer cells.

Gene silencing by CpG island methylation in the promoter region is one of the mechanisms by which tumor suppressor genes are inactivated in human cancers. It has been shown previously that Betaig-h3 gene, which encodes an extracellular matrix protein involved in cell adhesion and tumorigenesis, is down-regulated or silenced in a variety of human cancer cell lines. To unravel the underlying molecular mechanism(s) for this phenomenon, DNA methylation patterns of Betaig-h3 CpG island were examined in normal, immortalized, and cancer cell lines derived from lung, prostate, mammary, and kidney. A good correlation was observed between promoter hypermethylation and lost expression of Betaig-h3 gene, which was supported by the data that demethylation of promoter by 5-aza-2'-deoxycytidine reactivated Betaig-h3 and restored its expression in Betaig-h3-silenced tumor cell lines. This result was further substantiated by a luciferase reporter assay, showing the restoration of promoter activities and increased response to transforming growth factor-beta treatment in Betaig-h3-negative 293T cells when transfected with unmethylated Betaig-h3 promoter. In contrast, activity of Betaig-h3 promoter was completely inactivated by in vitro methylation. Furthermore, CpG methylation of Betaig-h3 promoter was also shown in primary lung tumors that expressed decreased level of Betaig-h3 protein. These results suggest that promoter methylation plays a critical role in promoter silencing of the Betaig-h3 gene in human tumor cells.

Azacitidine↗
PubMed2005

Lung adenocarcinoma global profiling identifies type II transforming growth factor-beta receptor as a repressor of invasiveness.

RATIONALE: Lung adenocarcinoma histology and clinical outcome are heterogeneous and associated with tumor invasiveness. OBJECTIVES: We hypothesized that invasiveness is associated with a distinct molecular signature and that genes differentially expressed in tumor or adjacent stroma will identify cell surface signal transduction and matrix remodeling pathways associated with the acquisition of invasiveness in lung adenocarcinoma. MAIN RESULTS: Microarray analysis of microdissected noninvasive bronchioloalveolar carcinoma (BAC) and invasive adenocarcinoma and adenocarcinoma-mixed type with BAC features identified transcriptional profiles of lung adenocarcinoma invasiveness. Among the signature set that was lower in adenocarcinoma-mixed compared with BAC was the type II transforming growth factor beta (TGF-beta) receptor, suggesting downregulation of TGFbetaRII is an early event in lung adenocarcinoma metastasis. Immunostaining in independently acquired specimens demonstrated a correlation between TbetaRII expression and length of tumor invasion. Repression of TGFbetaRII in lung cancer cells increased tumor cell invasiveness and activated p38 mitogen-activated protein kinases. Microarray analysis of invasive cells identified potential downstream mediators of TGFbetaRII with differential expression in lung adenocarcinomas. CONCLUSIONS: The repression of type II TGF-beta receptor may act as a significant determinant of lung adenocarcinoma invasiveness, an early step in tumor progression toward metastasis.

Adenocarcinoma↗
PubMed2005

P16 loss and mitotic activity predict poor survival in patients with peritoneal malignant mesothelioma.

PURPOSE: Peritoneal malignant mesothelioma is an aggressive neoplasm for which intensive therapy improves survival in a subset of patients. We hypothesized that pathologic variables would stratify patients into favorable and unfavorable survival subgroups. EXPERIMENTAL DESIGN: Fifty-four patients with peritoneal malignant mesothelioma were evaluated for trimodal therapy from 1995 to 2003. Two pathologists evaluated pathologic variables independently, and p16 status was analyzed by immunohistochemistry. RESULTS: Patients not receiving trimodal therapy had a significantly increased risk of death [hazard ratio (HR), 9.6; 4.3-21.6; P < 0.0001]. Biphasic histology was also associated with increased risk of death (HR, 8.5; 3.4-21.8; P < 0.0001). In multivariate analysis adjusting for treatment modality and histologic type, high mitotic rate and p16 loss were associated with increased risk of death (HR, 3.074; 1.05-9.0; P < 0.04 and HR, 3.65; 1.3-10.2; P < 0.014, respectively). CONCLUSIONS: Biphasic histology, increased mitotic rate, and p16 loss were independently associated with poorer survival in peritoneal malignant mesothelioma. Among the trimodal treated patients, increased mitotic rate was associated with increased risk of death.

Adult↗
PubMed2005

Utility of CD138 (syndecan-1) in distinguishing carcinomas from mesotheliomas.

CD138 (Syndecan-1) is a transmembrane heparan sulfate proteoglycan present on the surface of plasma cells and epithelial cells. CD138 is also expressed in some hematopoietic neoplasms and has recently been observed in carcinomas. We characterized CD138 expression in cell-block preparations of fluids/effusions, focusing on the distinction between carcinoma and mesothelioma. One hundred formalin-fixed, paraffin-embedded cell-block sections of fluids/effusions consisting of 58 metastatic carcinomas, 24 mesotheliomas, 11 reactive mesothelial cell proliferations, 3 lymphomas, 3 metastatic sarcomas, and 1 metastatic melanoma were stained with a monoclonal antibody against CD138. CD138 staining was observed in 32/58 (55%) metastatic carcinomas and 2/24 (8%) mesotheliomas; all reactive mesothelial cells, lymphomas, sarcomas, and melanoma were negative. CD138 is a highly specific marker in the differential diagnosis of carcinoma vs. mesothelioma. Distinct membranous staining without background staining of most inflammatory cells makes CD138 an ideal marker for cell-block preparations of fluids/effusions. It should be an integral component of the epithelial-mesothelial antibody panel.

Biomarkers, Tumor↗
PubMed2005

CDX2 immunostaining as a gastrointestinal marker: expression in lung carcinomas is a potential pitfall.

Paraffin-embedded sections of various adenocarcinomas (13 colonic, 11 mucinous ovarian, 5 serous ovarian, 8 pancreatic, 6 ampullary, 12 gastric, 5 esophageal, 10 endometrial, 29 breast, and 55 lung) and 29 additional lung carcinomas (nonadenocarcinomas) were immunostained with antibodies to CDX2 protein, cytokeratin 7 (CK7), and cytokeratin 20 (CK20). The 84 lung carcinomas were also stained with antibody to thyroid transcription factor-1 (TTF-1). All colorectal and most ovarian mucinous carcinomas were strongly and diffusely immunoreactive for CDX2. Esophageal, gastric, and ampullary adenocarcinomas showed variable immunoreactivity for CDX2. All breast, nonmucinous ovarian, and most endometrial and pancreatic adenocarcinomas showed no immunoreactivity for CDX2. CK7 and CK20 expression was similar to previous reports. Ten of 84 primary lung carcinomas (12%) were immunoreactive for CDX2 expression. Of these, 5 (4 adenocarcinomas and 1 large cell carcinoma) were reactive for TTF-1. Gene expression profiling data--available for 32 of these 84 tumors--showed CDX2 gene expression in 7 of 8 (88%) CDX2 immunoreactive tumors whereas only 1 of 24 (4%) tumors negative for CDX2 immunoreactivity showed CDX2 gene expression. The authors conclude that CDX2 is a relatively specific marker for tumors with intestinal differentiation, with the caveat that its expression can be seen in primary large cell and adenocarcinomas of the lung and mucinous carcinomas of the ovary.

Adenocarcinoma↗
PubMed2004

Expression of syndecan-1 and expression of epidermal growth factor receptor are associated with survival in patients with nonsmall cell lung carcinoma.

BACKGROUND: Recently, the authors identified molecular signatures and pathways associated with nonsmall cell lung carcinoma histology and lung development. They hypothesized that genetic classifiers of histology would provide insight into lung tumorigenesis and would be associated with clinical outcome when evaluated in a broader set of specimens. METHODS: Associations between patient survival and immunostaining for 11 representative histologic classifiers (epidermal growth factor receptor [EGFR], CDK4, syndecan-1, singed-like, TTF-1, keratin 5, HDAC2, docking protein 1, integrin alpha3, P63, and cyclin D1) were examined using a tissue microarray constructed from nonsmall cell lung carcinoma specimens. RESULTS: Sixty-three tumors were examined, including 43 adenocarcinomas, 11 large cell carcinomas, and 9 squamous cell carcinomas. Sixty-three percent of tumors were clinical Stage I lesions, and 37% were Stage II-III lesions. In a multivariate analysis that controlled for age, gender, and race, syndecan-1 expression was found to be associated with a significant reduction in the risk of death (hazard ratio, 0.31 [95% confidence interval, 0.18-0.87]; P < 0.05). Multivariate analysis also indicated that EGFR expression was associated with a significant reduced risk of death. CONCLUSIONS: The authors demonstrated that expression of either of the nonsmall cell lung carcinoma subtype classifiers syndecan-1 and EGFR was associated with a 30% reduction in the risk of death, with this reduction being independent of histology and other confounders. The results of the current study suggest that loss of expression of these histologic classifiers is associated with biologic aggressiveness in lung tumors and with poor outcome for patients with such tumors. If their significance can be validated prospectively, these biomarkers may be used to guide therapeutic planning for patients with nonsmall cell lung carcinoma.

Adenocarcinoma↗
PubMed2004

Molecular signatures in biopsy specimens of lung cancer.

Gene expression profiles of resected tumors may predict treatment response and outcome. We hypothesized that profiles derived from lung tumor biopsies would discriminate tumor-specific gene signatures and provide predictive information about outcome. Lung carcinoma specimens were obtained from 23 patients undergoing computed tomography-guided transthoracic biopsy or endobronchial brushing for undiagnosed nodules. Excess tissue was processed for gene profiling. We built class prediction models for lung cancer histology and for cancer outcome. The histology model used an F test to identify 99 genes that were differentially expressed among lung cancer subtypes. The histology validation set class prediction accuracy rate was 86%. The outcome model used the maximum difference subset algorithm to identify 42 genes associated with high risk for cancer death. The outcome training set class prediction accuracy rate was 87%. In conclusion, gene expression profiles of biopsy specimens of lung cancers identify unique tumoral signatures that provide information about tissue morphology and prognosis. The use of specimens acquired from lung biopsy procedures to identify biomarkers of clinical outcome may have application in the management of patients with lung cancer. The procedures are safe and feasible; the efficacy and utility of this strategy will ultimately be determined by prospective clinical trials.

Adult↗
PubMed2003

The heparan sulfate proteoglycan GPC3 is a potential lung tumor suppressor.

Recently, we used gene expression profiling of lung adenocarcinoma and paired normal tissue from smokers and nonsmokers to identify genes and molecular pathways associated with cigarette smoking and lung carcinogenesis. The gene encoding Glypican 3, a glycosylphosphatidylinositol-linked heparan sulfate proteoglycan, was decreased in lung adenocarcinoma. Within nonmalignant lung, GPC3 expression was decreased in smokers compared with nonsmokers; indicating that expression is associated with cigarette smoking. Microarray results were confirmed using an independent cohort of tumors and nonmalignant lung tissues. Immunohistochemical studies localized Glypican 3 protein expression to the apical surface of lung bronchiolar epithelial cells, potential cells of origin for adenocarcinoma. Northern blot analysis demonstrated expression was absent in all tested non-small cell lung carcinoma lines. Pharmacologic treatment of lung cell lines indicated that GPC3 expression was epigenetically silenced by promoter hypermethylation. Human lung carcinoma tumor cells ectopically expressing GPC3 demonstrated increased apoptosis response when exposed to etoposide and growth inhibition when implanted in nude mice. These findings suggest that GPC3 is a candidate lung tumor suppressor gene whose expression may be regulated by exposure to cigarette smoke and functions to modulate cellular response to exogenous damage.

Adenocarcinoma↗
PubMed2003

Non-small-cell lung cancer molecular signatures recapitulate lung developmental pathways.

Current paradigms hold that lung carcinomas arise from pleuripotent stem cells capable of differentiation into one or several histological types. These paradigms suggest lung tumor cell ontogeny is determined by consequences of gene expression that recapitulate events important in embryonic lung development. Using oligonucleotide microarrays, we acquired gene profiles from 32 microdissected non-small-cell lung tumors. We determined the 100 top-ranked marker genes for adenocarcinoma, squamous cell, large cell, and carcinoid using nearest neighbor analysis. Results were validated by immunostaining for 11 selected proteins using a tissue microarray representing 80 tumors. Gene expression data of lung development were accessed from a publicly available dataset generated with the murine Mu11k genome microarray. Self-organized mapping identified two temporally distinct clusters of murine orthologues. Supervised clustering of lung development data showed large-cell carcinoma gene orthologues were in a cluster expressed in pseudoglandular and canalicular stages whereas adenocarcinoma homologues were predominantly in a cluster expressed later in the terminal sac and alveolar stages of murine lung development. Representative large-cell genes (E2F3, MYBL2, HDAC2, CDK4, PCNA) are expressed in the nucleus and are associated with cell cycle and proliferation. In contrast, adenocarcinoma genes are associated with lung-specific transcription pathways (SFTPB, TTF-1), cell adhesion, and signal transduction. In sum, non-small-cell lung tumors histology gene profiles suggest mechanisms relevant to ontogeny and clinical course. Adenocarcinoma genes are associated with differentiation and glandular formation whereas large-cell genes are associated with proliferation and differentiation arrest. The identification of developmentally regulated pathways active in tumorigenesis provides insights into lung carcinogenesis and suggests early steps may differ according to the eventual tumor morphology.

Adult↗
PubMed2003

Patterns of allelic loss differ in lung adenocarcinomas of smokers and nonsmokers.

Cigarette smoking is the most important cause of lung cancer, however approximately 10% of patients with lung cancer have no history of smoking. While the molecular pathogenesis of smoking associated lung carcinogenesis is becoming well characterized, the pathogenesis of lung cancer in nonsmokers is not. We designed a study to examine the pathogenesis of adenocarcinoma in nonsmokers by determining if loss of heterozygosity (LOH) in tumors of nonsmokers differs from those of smokers. We evaluated six cases of primary adenocarcinoma in never smokers and six selected cases in smokers, matched by clinical and histological criteria. LOH in tumor DNA relative to nonmalignant lung DNA was determined at 52 microsatellites located on ten chromosomal loci. The extent of allelic loss in smokers, as measured by fractional allelic loss (FAL), was compared with nonsmokers. LOH was more frequent in the tumors of nonsmokers than of smokers with mean FAL of 46% in nonsmokers and 28% in smokers (P<0.05). Increased LOH in nonsmokers was most pronounced at chromosomes: 3p, 8p, 9p, 10p, and 18q. Since this study compared allelic loss between lung and tumor-bearing lung, less frequent LOH in smokers' tumors can be interpreted to suggest LOH was already present in the nonmalignant lung of smokers and fewer additional instances of allelic loss were present in the tumors of smokers. Our results suggest that the early steps of lung carcinogenesis differ in nonsmokers compared with smokers. In addition, the chromosomal sites of LOH may identify genes important for lung carcinogenesis in nonsmokers.

Adenocarcinoma↗
PubMed2003

Histologic assessment of non-small cell lung carcinoma after neoadjuvant therapy.

Chemotherapy or chemoradiation is often used in Stage IIIA non-small cell lung carcinoma before surgical resection (neoadjuvant therapy). In reviewing the histopathology of such tumors after resection, the recognition that the pathologic changes are related to prior therapy and the assessment of tumor regression are both of importance. To refine histologic parameters for tumor regression and describe patterns of tumor reaction to therapy, we identified 30 lobectomy or pneumonectomy specimens from 1996-2000 in which neoadjuvant therapy was received before surgical resection. Histologic patterns of treatment-induced tumor regression were analyzed semiquantitatively and included necrosis, fibrosis, mixed inflammatory infiltrate, foamy macrophages, and giant cells. To identify clinical and histologic parameters that correlate with treatment response, the 30 specimens were graded for tumor regression. No correlation was found between tumor regression and age, gender, or type of therapy (chemoradiation versus chemotherapy alone). Squamous cell carcinoma showed a significantly higher rate of response than adenocarcinoma (P =.04), with a significant number of adenocarcinomas in the nonresponder subgroup (P =.05). Tumor size reduction by radiologic assessment, when compared with histologic regression, did not reveal a statistically significant association. However, a positive correlation was found between extent of fibrosis and radiologic estimate of size reduction.

Adenocarcinoma↗
PubMed2003

Metastatic Leydig cell tumor of the testicle in a young African American male.

Malignant Leydig cell tumor (LCT) of the testis are extremely rare and account for less than 0.2% of all testicular cancers. Testicular tumors of all histological types rarely occur in African American men. The authors describe a rare case of an advanced stage malignant LCT arising from the testicle of an African American man at the young age of 35, who presented with hemoptysis and a productive cough. Clinical features and treatment of Leydig cell tumor of the testis are discussed.

Adult↗